Tavus a



(No Model.)

J. TARN & G. A. SGHURY.

ROCK DRILL STUFPING BOX.

No. 370,990. Patented Oct. 4, 1887.

UNITED STATES PATENT OFFICE.

JOHN TARN AND GUSTAVUS A. SOHURY, OF TARRYTOWN, ASSIGNORS TO GEORGE R. OULLINGXVORTH, OF NEYV YORK, N. Y.

ROCK-DRILL STU FFiNG-BOX.

SPECIFICATION torming part of Letters Patent No..370,990, dated October 4, 1887.

Application filedMay 1S, 1887. Serial X0. 2'l8,591. (No model.)

To aZZ whom it may concern.-

Be it known that we, JOHN TARN and GUs- TAVUs A. SCHURY, both of Tarrytown, in the county of Westchester and State of New York, have invented a new and useful Improvement in Devices for Locking the Glands of Rock- Drill Stuffing-Boxes, of which the following is a specification.

In rock-drills the piston-rod works through a stuffing box in the lower head, and the lower head and'lower gland which are fitted to the stuffing-box are frequently divided axially or made in sections, so as to be applied laterally to a pistonrod having formed integral with it at one end the piston and at the other end the chuck to receive the drill or bit. Owing to the rough usage and great shock which these machines receive in use, the stuffing-box gland constantly works loose; and the object of our invention is to provide a simple and effective means of looking or clamping the gland in place after it has been adjusted to proper position to confine the packing.

Our invention consists in the combination, with the piston-rod and the lower head of a rock drill constructed with a stuffing box, and a gland screwed into the box, both the head and the gland being divided axially, of bolts for securing together the sections of the head, and one of which is constructed with a shoulder forming a part of the bore, and in which the screw-thread of the box is continued, and which bears with a clamping ac tion on the periphery of the gland.

In the accompanying drawings, Figure l is a longitudinal section of such parts of a rockdrill as are necessary to illustrate our invention. Fig. 2 is a transverse section on about the plane of the dotted line a: as, Fig. 1; and Fig. 3 is an end View of the divided gland.

Similar letters of reference designateeorresponding parts in the several figures.

A designates the cylinder, and B the piston-rod, at one end of which it has formed integral with it the piston B, and at the other end of which is an integral enlargement, B", constituting the chuck in which the drill or bit is secured. The lower head of the cylinder A is axially divided, or is composed of two semicircular sections, 0 G, secured together by transverse bolts 0 C In the end of the lower head is formed a stuffing-box, a, screwthreaded to receive a gland, D, and in which packing d is pressed by the gland. The gland D is also axially divided, as shown in Fig. 3, and may have radial projections or spurs d, with which a wrench may be engaged 1or turning it into the stuffing-box c.

The bolt 0', which constitutes one of the bolts for securing together the sections of the head 0 is formed with a shoulder, c, as best shown in Fig. 2, and the hole through which this bolt is inserted is so near the bore of the stuffing-box that a portion of the bolt is cut away to form the shoulder, as represented best in Fig. 2, and in realityrforms a part of the bore or circular wall of the stuffing-box. The thread, which is out within the stufling-box c, is continued in the shoulder a of the bolt, and the screw-thread of the gland D engages the thread of the bolt as well as the thread of the stuffing-box. After the gland has been turned up to the required position into the stuffing-box '0, the nut 0 upon the bolt 0 is tightened, and the shoulder ,0 is thereby caused to exert a clamping action on the exterior of the gland, which prevents the gland from being turned by thejar and shock to which the machine is subjected in use. As here represented, the portion 0 of the bolt 0 which is above the shoulder c, is oflarger diameter than the portion below the shoulder and is eccentric to the latter portion; hence there is no tendency of the bolt to turn in its hole when a wrench is applied to the not 0', and the shoulder c is obtained where it is desired, and there is no shoulder on the opposite side of the bolt 0'.

By our invention we provide a very simple device for preventing the turning or unscrewing of the gland, and the clamping-bolt C may also perform service in holding together the sections (J of which the lower head is composed.

\Vhat we claim as our invention, and desire to secure by Letters Patent, is

The combination, with the piston-rod and with a clamping action on the periphery of the lower headof a rock-drill, and a gland the gland, substantially as herein described. screwed into the box, both the head and gland JOHN TARN. bein divided axially of bolts for securing 5 together the sections 0 f the head, and one of GUSTAVUS SGHURY' which,O is constructed with a shoulder form- Witnesses: ing a part'of the bore, and in which the screw- WARREN 0. BROWN,

thread of the box is c0ntinued,and which bears J NO. F. HOCTOB. 

